Ulykus
You can still do occupations and make some cats on your own, exploring another nice feature of ryzom as a side effect and getting plenty of consumables that help in grinding too. F2P players can also do some civ faction runs to get additional cats (and sap crystals).
During the Q&A session yesterday, we were told that there would be no cats from any sources, not just OPs. This was from the Event Guide; so, he may have it wrong as the post only indicates OPs don't produce cats...will be interesting to see how that plays out.
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Eldest, Order of the White Lotus